Hemodialysis solution must be produced for hemodialysis based on an electrolyte content essentially corresponding to that of the blood of a patient to be treated.
Hemodialysis removes toxic substances and metabolic waste from the bloodstream using an extracorporeal circuit with components designed to perform ultrafiltration and diffusion on the blood. Before the blood is returned to the body, air bubbles are removed from the blood to inhibit embolisms.
Dialysis is performed as a treatment for patients suffering from renal insufficiency. This is performed either in the peritoneum or through extracorporeal dialysis or filtration of blood. These two methods have in common the fact that dialysis fluids or dialysates take up the degradation products of metabolism. These dialysates usually contain high levels of sodium chloride and other electrolytes such as calcium chloride or potassium chloride, a buffer substance such as bicarbonate or acetate and acid to establish a physiological pH plus optionally glucose or another osmotic agent.
Dialysates are either supplied as ready-to-use solutions or they are prepared on site from concentrates, including solid concentrates. Solids offer the advantage of a small package volume and a low weight. Although solids also have disadvantages—electrolyte salts, for example, are highly hygroscopic—there is a trend toward offering only solid components for preparation of dialysates.
During hemodialysis using systems such as described in U.S. Pat. No. 5,385,564 and U.S. Pat. No. 5,616,305, incorporated by reference herein, dry bicarbonate or acid concentrate is mixed with dialysate via a container using one or more ports. Even when the container is filled there is always air remaining in the container. The system cannot remove all of the air from the container without evacuating the air from the container via a vacuum system to create negative pressure, before filling the container with water. The present invention provides a solution to the air problem in the container without the use of a vacuum system, and will allow air to be removed from the bag during the initial fill with bicarbonate or other compound, such that the container can be optimized or reduced in size which allows for improved mixing with a smaller container.